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Paint system to dissipate heat from control cabinets

What paints to be used to paint outside and inside surfaces of totally enclosed control cabinets to improve heat dissipation by emmisivity or by radiation when internal cooling fans can not be put inside to provide forced cooling within the control cabinets?

Prashant Marathe
Government service in R & D application for control drives. - Mumbai, Maharashtra, India
2004

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I am interested to hear an answer to this myself, Prashant, but I'm betting you won't like it because I think you'll find that the difference in heat transfer from the worst paint to the best will be lost to roundoff error. Heat sinks, air conditioning, and similar techniques can be employed for heat dissipation from enclosed cabinets.

Ted Mooney, P.E.
Striving to live Aloha
finishing.com - Pine Beach, New Jersey
2004

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Right on, Ted! For anything that close to ambient temperature, radiation is a tiny fraction of the total heat transfer. For a cabinet in still air and no internal fans the thermal conductance is about 1 BTU/Hr./degree F/Sq.Ft. of exposed surface. With 'substantial' internal fans that goes to 2/BTU/Hr/degree F/Sq.Ft. Anything more than that requires either an air-to-air heat exchanger or an air conditioner. The major U.S. enclosure manufacturers show both in their catalogs. For instance the www.hoffmanonline.com site has a free program download to size the coolers.

Tom Gallant
- Long Beach, California, USA
2004